Republicans are arguing over what the United States should do about Syria – with Democrats, of course, but more significantly with themselves.

Leading the more hawkish wing is Sen. John McCain, who knows something about war firsthand and is not always in line with his party’s deep thinking on the way to confront foreign enemies (see the efficacy of “enhanced interrogation,” otherwise known as torture).

But Senator McCain is just back from Syria, where he met with some of the rebels trying to overthrow the regime of Bashar al-Assad in a bloody conflict that’s cost tens of thousands of lives. And speaking on CBS’s “Face the Nation” Sunday, the Arizona Republican once again called for the US and its allies to send missiles and bombs into the fray.

"We need to give them a no-fly zone," McCain said, speaking of rebel forces. "The Israelis have shown us we can take out their facilities from a distance, that we don't have to risk our pilots. We can crater their runways, we can take out their air assets, we can provide them with a safe zone….”

“We can establish that safe zone," he said, "and I'm confident that we can prevail."

Such thinking does not appeal to the more isolationist, libertarian wing of the GOP – namely Sen. Rand Paul, who (like his father Ron Paul before him) could be a force in the 2016 presidential race.

“I’m very worried about getting involved in a new war in Syria,” he said. “People say, ‘Assad is such a bad guy.’ He is. But on the other side we have Al Qaeda and now Nusra,” militant groups fighting with the Syrian opposition.

“They say there are some pro-Western people and we’re going to vet them,” Paul continued. “Well, apparently we’ve got a senator over there who got his picture taken with some kidnappers, so I don’t know how good a job we’re going to do vetting those who are going to get the arms.”